Continuously moving ballast removing mechanism



Oct. 1, 1968 M. J. SPENO 3,403,462

INVENTOR W Afrom;

MET/N J Spa/0 Oct. 1, 1968 M. J. SPENO 3,403,462

CONTINUOUSLY MOVING BALLAST REMOVING MECHANISM Filled Dec. 6, 1965 2Sheets-Sheet 2 INVENTOR, MAN/NJ .S'PENO Z/afm, m wz fan/ 64 ATTORNEYSUnited States Patent 3,403,462 CONTINUOUSLY MOVING BALLAST REMOVINGMECHANISM Martin J. Speno, Syracuse, N.Y., assignor to Frank SpenoRailroad Ballast Cleaning Company, Inc., Ithaca, N.Y.,

a corporation of New York Filed Dec. 8, 1965, Ser. No. 512,460 15Claims. (Cl. 37-104) ABSTRACT OF THE DISCLOSURE Mechanism forautomatically removing dirty ballast from between the adjoining ties ofa railroad track, in which a portable vehicle movable along the trackcarries a plurality of probes for vertical projection and retractionmovement into the ballast between the cribs. Proximity switches actuatedby the tie plates of the respective ties, control solenoid actuatedvalves which, in turn, cause the probes to be projected downwardly intoand withdrawn from the crib spaces as the vehicle moves along the track.The probes are provided with cam faces to laterally displace the ballastand also are provided with laterally directed jet nozzles for emittingjets of pressurized fluid for laterally displacing the ballast.

This invention relates to mechanism for automatically removing dirtyballast from the cribs or spaces between relatively adjoining ties of arailroad track.

It has been heretofore known to employ a mechanical means for digging orraking the ballast outwardly from the cribs. However, such a mechanicalmeans has either necessitated the lifting or raising of the rails orelse has involved extremely heavy and complicated parts. Similarly, ithas heretofore been known to employ blasts of fluid such as gases orliquids under high pressures for removal of the ballast. However, in sodoing, difficulty has been encountered in securing the desired degree ofpenetration of the packed ballast, as well as in controlling the depth,shape and extent of the resulting excavation.

With these considerations in mind, the primary objects of the presentinvention are to combine both of said old principles in a singlemechanism which accordingly employs a mechanical digging and lateraldisplacing action in combination with a blast jet or jets of fluid athigh pressure to remove the ballast from the cribs in a particularlyefiicient and rapid manner; to provide such a mechanism which is adaptedfor removal of ballast from successive cribs while in constant motionalong the track, without damage to the ties; to provide such a mechanismwherein the mechanical digging or excavating means is automaticallyprojected downwardly into each crib to a predetermined depth and rapidlyretracted during its movement between each pair of adjacent ties.

Further, it is an object to provide each of the mechanical digging orexcavating members of the mechanism with one or more laterally directedjet orifices and means for delivering fluid therethrough at highpressures and velocities during the penetration of such member into theballast whereby to propel or displace the ballast outwardly laterallyfor reception alongside the pump track, preferably in a preformed ditchor trench paralleling the track. It is a further object to provide meansfor auto- 3,403,462 Patented Oct. 1, 1968 matically discontinuing thesaid blast jet as its associated probe or excavating member isretracted.

Still further it is an object to employ a plurality or gang of the saidprobes or members in series, so as to follow each other in relativelylaterally offset relation, preferably at uniform lateral distances, witheach probe displaced uniformly laterally inwardly from the probeimmediately in advance thereof in the direction of travel of the ballastremoving car or vehicle, so that the ballast will be removed from eachcrib in successive increments from the outer extremity inwardly thereof.It is also an added feature to provide the respective probes withinclined cam faces arranged to mechanically displace the ballastlaterally outwardly incident to their penetrating movement into theballast.

The foregoing and other incidental objects and advantages will all bereadily apparent. from a consideration of the following detaileddescription, together with the accompanying drawings of a preferredembodiment of the invention in which:

FIGURE 1 is a view in perspective, showing a portion of a conventionalrailroad flatcar and of the underlying conventional railroad track uponwhich it is guided, a preferred exemplification of the invention beingsupported from the car for operation on the ballast between the outerends of the ties;

FIGURE'Z is a vertical cross section through the structure shown inFIGURE 1;

FIGURE 3 is a view partly in plan and partly in section on the line 3-3of FIGURE 2, showing the relatively offset or staggered relationships ofthe ballast removing members or probes;

FIGURE 4 is an enlarged diagrammatic view, partly in section and partlyin elevation, showing the hydraulic and electrical control circuits andvalve means employed in conjunction with each of the said probes; and

FIGURE 5 is a detail elevation on theline 5-5 of FIGURE 4, showing atypical disposition of the jet defining orifices in the lower ballastpenetrating end portion of the probe.

To promote an understanding of the invention, reference will now be madeto the preferred embodiment thereof illustrated in the accompanyingdrawings, and specific language will be used to describe the same. Itwill nevertheless be appreciated that no limitation of the scope of theinvention is thereby intended, but that such further modifications andalterations are envisioned as would normally occur to one skilled in theart to which the invention relates.

Referring now to the accompanying drawings, there is illustrated inFIGURES 1 and 2 a fragmentary portion only of a conventional fiatcar 10,including a portion of the side rail 11 and of the flat load carryingbed 12 thereof. As is well known, such a car is normally supported andguided for movement along the railroad track by conventional flangedwheels (not shown), each which is adapted for engagement with a rail 13of the track.

The rails 13 are secured by conventional tie plates T on cross ties 14which are partially embedded in the ballast 15. The ballast generallyconsists of crushed stone, or the like, which over a period of timetends to become intermixed with dirt and foreign material which clogsthe interstices between adjoining stone particles to an extent whichinterferes with proper drainage and otherwise is undesirable.

It is accordingly the practice to remove, clean and replace the dirtyballast whereby to restore the roadbed to its proper operativecondition. While the ballast alongside t'he outer ends of the ties mayreadily be removed by conventional scoop means, transported alongthetracks in a manner to remove such ballast and to leave a trench alongthe tracks to be subsequently filled by clean ballast, the presentinvention is directed to the more diflicult problem of removing dirtyballast from. the cribs or spaces between the adjoining ties. Themechanism here illustrated is especially adapted for removing suchballast from between the outer ends of the ties, laterally outwardly ofthe rails, though it is by no means restricted to use in ballast removedat this location.

Generally speaking, the invention is embodied in one or more probes 16,guided for rapid vertical penetration into and Withdrawal from the cribsby means of fluidpressure actuated cylinders 17, here shown as carriedby common rigid frame bar 18 supported from the flatcar in a normallystationary position. Preferably the bar 18 is carried by a series ofvertical guide rods 20 which are telescopically received within theguide sleeves 21 respectively for vertical adjustment of the frame 18.For the purpose of lateral adjustment, the respective sleeves 21 areeach supported by -a horizontal guide rod 22 for telescopic slidingreception in a guide sleeve 23 supported from the bed 12 of the car by asuitable bracket 24. The vertical guide sleeves 21 are interconnected byrigid longitudinal bar 25, through which lateral adjustment istransmitted to the sleeves 21 and frame 18 from a suitable hydraulic,pneumatic or other conventional power actuated means, through the rigidlinks 26 having their clevises 27 connected to cooperating arms 28affixed to the bar 25.

As will be apparent from FIGURES 1 and 2, the cylinders 17 of therespective fluid pressure actuated means or devices are supported fromthe frame bar 18 by rigid horizontal arms 30 respectively. Fluidactuated cylinder and piston units 3131, operatively interconnectedbetween certain of the arms 30 and rigid arms 32 of the connecting bar25, exemplify convenience means for selectively adjusting the verticalposition of the frame 18 and securing it in the desired position ofadjustment. Thus the entire gang of probes 16 supported from the frame18 may be vertically and horizontally adjusted to any of various desiredoperative positions relative to the roadbed. For transport purposes, theframe 18 normally will be fully raised by action of the piston andcylinder units 31 and displaced or drawn laterally inwardly closelyadjacent to the side sill 11 by traction forces transmitted through theconnecting rods or links 26.

Referring now to FIGURE 4, in conjunction with FIGURES 1 and 2, eachprobe 16 in the present embodiment comprises a rigid hollow tube,terminating at its lower ballast engaging and penetrating end in acomparatively sharp edge 34 adapted to facilitate its penetration of theballast. Preferably, each probe has a vertically inclined cam face 35sloping upwardly and outwardly, away from the rail 13, so that it willtend to mechanically displace the ballast in a laterally outwardlydirection for reception in the trench D adjacent to the outer ends ofthe ties. Opening outwardly through this cam face 35 are one or moreorifices 36 communicating with its hollow interior and adapted to besupplied with pressurized fluid such as steam, compressed air, exhaustgases of a jet engine or the like, whereby late-rally directed jetstreams will'be caused to issue at high velocity through the respectiveorifices to propel the ballast outwardly from the cribs and into trenchD.

In the present embodiment, the shank 37 of each probe 16 extends and isslidable completely through the opposite ends of its associated cylinder17, whereby fluid at the desired pressures and in the desired volume maybe readily supplied through the hollow interior of each probe 16 to itsorifices 36 by means of a flexible conduit 38 clamped to the upper endof its shank 37 as at 39.

The shank 37 is encircled by and fixedly connected to the annular piston40 which in turn is disposed for move ment in the cylinder 17 in snugfluid-tight sliding engagement with its inner peripheral walls, wherebyvertical movement may be imparted to the probe 16 by fluid pressurewithin the cylinder acting against the piston.

The pressurized fluid for causing the downward stroke of the piston 40is admitted into the cylinder 17 above the piston through one or moreconstantly open ports 42 opening radially outwardly from the hollowinterior of the pro-be shank 37 above the piston. 'Thus the samepressurized fluid which is delivered through the hollow shank 37 to thejet orifices 36 will provide the actuating pres sure for the downward orpenetrating stroke of the piston 40 and probe 16 simultaneously with theopening of a valve or the like for permitting flow of the pressurizedfluid to the probe 16.

The raising or retraction stroke of the probe16, which occurs only afterthe discontinuance of the fluid supply through the hollow probe shank37, is produced by intro duction of pressurized fluid into the lower endof the cylinder 17 beneath the piston 40 through the inlet passage 43,the port 42 then serving as an exhaust port. For permitting the exhaustof gases from the lower portion of the cylinder during the down strokeof the piston 40, the inlet port 43 is in communication with an exhaustport 44, through a shuttle valve 45 which is normally biased by thespring 46 to a position in which it places the passages 43 and 44 incommunication with each other. However, the fluid pressure for raisingor retracting the piston 40 is delivered to its inlet passage 43 througha flexible conduit 47 which communicates with the shuttle valve 45 in aknown manner such that the pressure of fluid when admitted to theconduit 47 moves the valve 45 downwardly to compress its spring 46 andto close the exhaust passage 44, while placing the conduit 47 incommunication with the inlet 43. It will be appreciated that immediatelyupon cessation of the fluid pressure within the conduit 47, the spring46 will return the valve 45 to its original position to permitexhaustion of the fluid from the lower portion of the cylinder incidentto the next downward stroke of the piston 40.

Preferably the flexible fluid conduits 47 and 38 are arranged foralternate communication through the control valve 48, 'with a supplyline or manifold 53 for fluid under pressure. The valve 48 is controlledby solenoids in the manner taught in the United States patent of Mc-Guire 1,024,250 of Aug. 29, 1933. Thus the body of the valve 48 ispositioned by means of its stem 49. A compression spring 50, reactingbetween an enlargement 51 on the stem 49 and the valve housing, normallybiases the valve to a position in which a supply of fluid from the line53 or other suitable source of such fluid under pressure is delivered tothe conduit 47 to maintain fluid pressure beneath the piston 40 and thusto normally maintain the piston 40 and its associated probe .16 in fullyraised position. The valve stem 49 is of a magnetizable material. Itconstitutes the core of a solenoid, the winding 54 of which is energizedunder the control of a generally conventional and normally openproximity switch 55 which is carried by the frame 18 for movement in apath which extends above the respective tie plates T and in suchtrailing relation to its associated probe 16 as to be closed by itsproximity to each tie plate as or shortly after the probe 16 is carriedover and free of the particular tie 14 with which the said tie plate isassociated. The switch 55 remains thus closed throughout the duration ofits movement above the tie plate, whereupon it will auto matically openin a manner well known to those skilled in the art, the switch beingactuated by the magnetic attraction of the tie plate, or if desired byphysical contact with the tie plate.

In the preferred embodiment, the switch 55 is carried by a bracket 56,which is laterally positioned on the track by means of a roller 57having flanges at its opposite ends to effect such positioning. The saidbracket or carriage is propelled along the rail 13 by virtue of itsconnection through a cross pin 58 to a depending coupling member 60carried by the frame bar 18. The cross pin 58 is freely slidable throughthe member 60 to afford freedom of lateral movement so that the lateralposition of the switch 55 at one side of the rail may be accuratelydetermined by its flanged roller 57.

Thus, as the proximity switch 55 for a given probe 16 is closed incidentto its passage over a tie plate T, the probe 16 will have cleared thetie. The ensuing energizing of the solenoid coil 54 and the actionthereof on the valve stem 49 moves valve 48 to disrupt the communicationbetween the supply conduit 53 and the retraction conduit 47 and to placethe supply conduit 53 in communication with the conduit 38, therebysimultaneously initiating the operative downward stroke of the pistonthrough the entry of pressurized fluid into the upper portion of thepiston through inlet ports 42, and also the discharge of jets ofpressurized fluid at high velocity through the orifices 36 of the probe.The valve 48 will be latched into its said position by the reception ofthe spring projected latch member 63 in its coacting latching notch 64.The latch member 63 constitutes the movable core of a solenoid 65 fromwhich the latch 63 is normally spring projected to latching engagementwith the valve stem 49.

V The circuit 66 to and through the solenoid 65 is controlled by limitswitch 67 positioned on the bottom of the cylinder 17 so as to be closedby the downwardly moving piston 40 at the lower end of its operativestroke. Thus, closing of the limit switch 67 at the lower end of thepiston stroke 40 will energize the coil of solenoid 65 to retract thelatch 63, thereby permitting return of the valve 48 under the action ofits valve spring to its original position in which the fluid supplyconduit 53 is disconnected from the conduit 38 and placed incommunication with the retraction conduit 47. The shuttle valve 45 whichwill have been positioned by spring 46 to permit exhaust of fluid fromthe lower portion of the cylinder during its down stroke, will now beactuated by the fluid pressure in conduit 47 to place said conduit incommunication with the lower portion of the cylinder through passage 43,while closing off the exhaust passage 44. Such pressure beneath thepiston 40 will cause the upward retraction of the probe 16, the fluid inthe upper portion of the cylinder then being exhausted into the hollowprobe shank 37 through the port 42 and dis- 7 charged through theorifices 36.

It is to be understood that the various parts will so be proportionedand interrelated that the downward stroke of the probe and its upwardretraction will occur quite rapidly, while the fiatcar 10 is movingalong the rails at a rate of speed, and without interruption of suchmovement. In other words, the rejection and retraction stroke will betimed to occur during the interval required for movement of the probe 16across the space from one tie to the next and will normally allow amplemargin for action between irregularly spaced or unusually closely spacedties.

Subsequent to each retraction, a given probe 16 Will remain raisedduring passage over the next tie, due to the continuing transmission offluid pressure to the lower portion of its cylinder 17, the position ofthe valve 48 remaining unchanged until its solenoid 54 is againenergized by the proximity switch 55 in passing over the tie plate T ofthe next tie. As will be apparent, the leading probe 16 with respect tothe movement of the fiatcar 10 (as indicated by the arrow in FIGURE 1)is spaced laterally outwardly from the side of the car 10 for movementin a path near the outer extremities of the ties 14 and just inwardlyfro-m the adjoining vertical edge of the trench D. The trailing probes16 are supported in positions successively closer to the car 10 and thusare successively placed inwardly at progressively greater distances fromthe ends of the ties and the adjacent wall of trench D. It will beappreciated that each probe is automatically actuated independently ofthe others, so that each in turn will act upon all cribs, and that theseveral probes will each remove from a given crib an increment orportion of the ballast, whereby the several probes, by their successiveaction on each crib, will remove the total intended amount of ballasttherefrom in successive increments of substantially uniform size and toa uniform depth, corresponding to the uniform depth to which the probes16 are projected on their penetrating or downward stroke.

Such depth of penetration for all of the several probes may becontrolled or regulated by appropriate position of their supportingframe bar 18, by means of the fluid actuated cylinder and piston units31. Similarly, the lateral position of the frame 18 and thus the lateraloperating positions of the probes 16 may be adjusted toward and awayfrom the rail 13 as desired.

The actuation of the several probes 16 thus is automatically initiatedimmediately after each probe passes over a tie. The ensuing downwardprojection of the probe and actuation of its blast jets, and thesubsequent retraction of the probe, occur substantially instantaneouslyso that the probe will be raised clear of the next tie to pass thereoverbefore being again actuated. Thus, the probes 16 normally will be guidedand actuated in such a manner as to avoid collision with the ties.However, as an added safeguard, the probes 16 are each connected to itsrespective shank 37 along an encircling weakened zone, such as 68 inFIGURES 4 and 5, located just below the internal check valve seat 69. Aball check valve 70 is supported above theseat 69 by a bracket 71secured to the inner wall of the probe 16. In the event of breaking awayof the probe along weakened zone 68, the ensuing seating of the checkvalve 70 will prevent the uncontrolled escape of the pressurize-d gasfrom the lower end of shank 37.

As has been above indicated, the foregoing detailed description andaccompanying drawings, through directed specifically to the preferredembodiment of the invention, are merely by way of exemplification of theinvention, and various changes and departures from such preferredembodiment are contemplated within the scope of the appended claims.

Having thus described my invention, I claim:

1. Mechanism for automatically removing ballast from between adjoiningties of a railroad track, comprising a portable vehicle adapted formovement parallel to the rails of said railroad track, a rigidsupporting frame on said vehicle, a plurality of probes supported bysaid frame for vertical projection and retraction movement into and frompenetrating engagement with the ballast in the crib spaces betweenadjacent cross ties of the track, fluid pressure actuate-d means forraising and lowering the respective probes, valve means for controllingsaid fluid pressure actuated means, sensing means operative in responseto the movement of each said probe into vertical registry with a cribspace for rapidly downwardly projecting and retracting said probe duringits movement in registry with said space, and means for retaining saidprobe in its raised position until again actuated by said sensing meansincident to its movement with the portable vehicle into verticalregistry with a further crib space, said sensing means comprising aproximity switch carried by said vehicle for movement along a pathoverlying the tie plates of the respective ties and in predeterminedtrailing relation to its associated probe, to be closed incident topassing over each tie plate, and solenoid means operatively connected toand controlling said valve means, said solenoid means being in circuitwith and controlled by said sensing means.

2. Automatic mechanism as recited in claim 1, in which each said probeis provided with a sharpened lower end for penetration of the ballastand with a cam face presented outwardly away from the said vehicle, saidcam face being inclined upwardly and laterally outwardly to displace theballast laterally outwardly incident to penetration thereof by the saidprobe.

3. Mechanism for automatically removing ballast from between adjoiningties of a railroad track, comprising a portable vehicle adapted formovement parallel to the rails of said railroad track, a rigidsupporting frame on said vehicle, a plurality of probes supported bysaid frame for vertical projection and retraction movement into and frompenetrating engagement with the ballast in the crib spaces betweenadjacent cross ties of the track, fluid pressure actuated means forraising and lowering the respective probes, valve means for controllingsaid fluid pressure actuated means, sensing means operative in responseto the movement of each said probe into vertical registry with a cribspace for rapidly downwardly projecting and retracting said probe duringits movement in registry with said space, and means for retaining saidprobe in its raised position until again actuated by said sensing meansincident to its movement with the portable vehicle into verticalregistry with a further crib space, said sensing means comprising aproximity switch carried by said vehicle for movement along a pathoverlying the tie plates of the respective ties and in predeterminedtrailing relation to its associated probe, to be closed incident topassing over the tie plate, and solenoid means operatively connected toand controlling said valve means, said solenoid means being in circuitwith and controlled by said sensing means, said plurality of probesbeing arranged in relatively staggered relation, with the leading saidprobe relative to the direction of the vehicle movement being supportedat a maximum lateral distance outwardly from the said supporting frame,and the other said probes being successively located in a manner suchthat each is inwardly laterally displaced with respect to the probe inadvance thereof, said fluid pressure actuated means for raising andlowering the respective probes being independently operable with respectto each said probe, whereby the said plurality of probes will act insuccession upon each crib space to remove ballast therefrom insuccessive increments from the outer end of the crib space inwardlytoward the rail.

4. Automatic mechanism as recited in claim 3, wherein each said probeincludes a laterally outwardly directed jet nozzle adjacent its lowerend and means for supplying pressurized fluid to said nozzle forissuance therefrom as a jet for displacing the ballast on the outer sideof said probe.

5. Automatic mechanism as defined in claim 1, in which each said probeis provided with an orifice opening laterally outwardly through itslower end and a fluid supply passage communicating with said orifice,means being provided for supplying pressurized fluid to said passage foremission through said orifice in the form of a laterally outwardlydirected fluid jet.

6. Automatic mechanism as defined in claim 5, including means operativein the raised position of said probe for discontinuing the flow of fluidto said orifice.

7. Mechanism for automatically removing ballast laterally outwardly fromthe cribs of a railroad track, comprising a portable vehicle adapted formovement along and parallel to the rails of the track, a supportingframe carried by said vehicle, a plurality of probes supported by saidframe for independent vertical downward projection and retractionwhereby to cause their lower ends to penetrate the ballast in the cribsto predetermined uniform depth, fluid pressure actuated means forraising and lowering the respective probes, valve means for controllingthe projection and retraction of each probe, sensing means operativelyconnected with each said valve means for initiating the projectionstroke of the probe each time the same reaches a position of verticalregistry with a crib, each of said probes being provided adjacent itslower end with a laterally directed orifice and including a passage forconducting pressurized fluid to said orifice, and means for supplyingfluid at high pressure to said passage for ejection through said orificeto be discharged therethrough in the form of a laterally out wardlydirected jet stream.

8. Automatic mechanism as defined in claim 7, including valve meanscontrolling the flow of fluid through said passage, said valve meansbeing operatively connected to said sensing means to be opened duringeach downward projection of the probe.

9. Automatic mechanism as defined in claim 8, including means controlledby said projection of the probe for closing said valve means todiscontinue said fluid jet at a predetermined point in the downwardprojection stroke of the probe.

10. Automatic mechanism as defined in claim 7, in which said fluidpressure actuated means for each said probe comprises a fluid actuatedpiston and cylinder unit in which the probe is carried by the pistonthereof.

11. Automatic mechanism as defined in claim 10, in which said sensingmeans comprises a proximity switch carried by said vehicle for movementalong a path overlying the tie plates of the respective ties and inpredetermined trailing relation to its associated probe, to be closedincident to passing over the tie plate, solenoid means operativelyconnected to and controlling said valve means, said solenoid means beingin circuit with and controlled by said sensing means.

12. Automatic mechanism as defined in claim 11, in which said valvemeans for controlling the fluid pressure actuated means, and said valvemeans for controlling the flow of pressurized fluid to the orifice ofsaid probe, both comprise a valve common to both said fluid pressureactuated means and said valve means.

13. Automatic mechanism as defined in claim 11, including a normallyopen limit switch in position for operative engagement by said pistonnear the lower extremity of its downward movement, and means for closingthe said valve means to permit retraction of the said probe, said meansincluding a solenoid having a coil in circuit with said limit switch.

14. Automatic mechanism as defined in claim 13, including means definingand alternately acting inlet and discharge passage communicating withthe lower end portion of said cylinder beneath the piston therein, ashuttle valve normally spring biased to a position to place said passagein communication with the atmosphere, 2. fluid supply conduitcommunicating with said shuttle valve and arranged to apply fluidpressure against said valve for actuating same to close said exhaustpassage and to place said supply passage in communication with the inletpassage, and a solenoid valve having a control switch positioned foractuation by said piston near the lower end of the stroke for admittingpressurized fluid to such supply passage for retracting the said piston.

15. Mechanism for operating automatically and successively on fixedcomponents of a railroad track structure, comprising a carrier disposedfor movement along said structure, a tool supported by said carrier formovement transversely to the movement of the carrier for successiveoperative engagement with and disengagement from said components, fluidpressure means for so moving the tool relative to said components, valvemeans for controlling said fluid pressure means, sensing means actuatedin response to the positioning of said tool adjacent each said componentincident to movement of the carrier for thus transversely moving thetool relative to each of said components in succession, and means forretaining said tool disengaged from said components between actuationsof the sensing means, said sensing means comprising a proximity switchcarried by said vehicle for movement along a path overlying the tieplates of the respective ties and in predetermined trailing relation toits said tool,

to be closed in response to passing over each tie plate, and solenoidmeans operatively connected to and controlling said valve means, saidsolenoid means being in circuit with and controlled by said sensingmeans.

References Cited UNITED STATES PATENTS 2,028,688 1/1936 Rugg et a1.17116 XR Philbrick 37104 McWilliams 37-104 Hursh et al. 37104 Bach eta1. 37104 XR Kershaw 37104 XR ROBERT E. PULFREY, Primary Examiner.

E. S. BURR, Assistant Examiner.

